Swivel closure for rotatable containers



April '4,- 1961 2,978,004

D. F. SMITH SWIVEL CLOSURE FOR ROTATABLE CONTAINERS Filed June 11, 1959 INVENTOR SWIVEL CLOSURE non RQTATABLE 'CON-TAINERS Donald F. Smith, Holliston, Mass, assignor to the United States of America as rcpresented'by the Secretary of the Army The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes, without the paymentto me of any royalty thereon.

The present invention relates to improvements in closures for rotatable containers, and more particularly to a swivel closure for a flexible container.

An important object of the present invention is th provision of a swivel closure for a flexible container which will permit rotation of the container about its axis, like a roller or wheel, for towing or moving the container about.

Another object of the invention is the provision of a closure of this type provided with a fitting for engagement with lifting or securing devices so that the container may be easily handled, moved, secured in a desired position, or dropped by parachute.

Still another object of the invention is to provide a closure of this character with means forfilling or empty- 7 ing the container.

A further object of the invention is toprovide a closure of this character which is of simple and inexpensive construction, strong and durable in use, and easily secured to the flexible material of the container.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings which form a part of this sepciiication and wherein like numerals desginate like parts throughout,

Figure 1 is a side elevation of a flexible container embodying the present invention, parts being broken away;

Figure 2 is a top plan view of the swivel closure;

Figure 3 is a transverse sectional view of the closure taken on the line 3-3 of Figure 2; and

Figure 4 is an enlarged fragmentary detail sectional view of the rim portion of the outside retaining plate of the swivel closure.

In the drawings, wherein for the purpose of illustration is shown a preferred embodiment of the invention, the numeral denotes a container which may be of any suitable construct-ion and shape but is shown as of generally drum or cylindrical shape with rounded corners. The container is flexible and collapsible and may be formed of coated fabric plies or any other suitable material having the necessary strength and flexibility. ,Containers of this type are used commercially for trans: porting liquids and other fluent materials, and, when emptied, can be collapsed for return or storage. The containers vary in size but some are very large, having a capacity of several hundred cubic feet, and in order to withstand high internal pressures and maintain their shape, their ends are connected internally by a cable in smaller drums or .by aplurality of cables in large drums which may be centrally connected as shown at 11 in Figures 1 and 3. The construction of the container lit], as time far-described, forms no part of the present inn 9nr A similar closure assembly is provided at each end of 2.97am Patented Apr. 4,1961

the drum, and for convenience the upper assembly of Figure 1 will be described. Each closure assembly comprises an inside cable plate 12, which is preferably circular in shape and provided with a plurality of inwardly extending cable anchoring knobs 1-3 into which the ends of the cables 11 are anchored in any suitable manner, as by means of sleeves 14 welded to the ends of the cables and received in sockets provided in the knobs 14. The knobs 13 are spaced around the lower or inner face of the cable plate 12 adjacent its periphery, and a central sleeve 15 may surround the central portions of the cables as shown in Figure 1, although any other suitable arrangement of the cables and their anchoring means may be employed. The cables 11 connecting the two plates 12 maintain the shape of the container against internal pressures.

An outside retaining ring 16 is provided with an annular series of bolts 17 adapted to pass through'a similar annular series of openings in the material of the end of the container and into an annular series ofscrew-threaded recesses in the outer surface of the inner cable plate 12. The under surface of the retaining ring 16 which engages the material of the container may be serrated or roughened as at 18. The inner annular lower peripheral edge of the retaining plate 16 is undercut at 19 to form an annular recess for the reception of a lower radially projecting flange 20 on an outer bearing ring 21. The bearing ring 21 has a thickness substantially equal to the combined thickness of the retaining ring 16 and the material of the container wall when such wall is compressed between cable plate 12 and retaining ring 16 by means of bolts l7. The bearing ring 21 preferably has a press fit in retaining ring 16 'and' is held therein by engagement of radial flange 20 in undercut recess 19, as seen in Figure 3 of the drawing, but it could be formed integrally with the clamping ring 16 if desired.

The inner peripheral face of the ring 21 is inclined so that it forms a frustum of a cone with its base in the lower plane of the ring 21 and its walls converging away from its base to provide an annular reentrant or undercut bearing surface to engage a complementary surface on a swivel member 22. The bearing surface of ring 21 may be of any suitable angle to maintain the swivel member against axial movement upwardly out of ring 21 while permitting ready rotation of the swivel member within the ring 21. An angle of 20 with respect to the axis of the bearing ring has been found to be satisfactory for this purpose, but obviously this angle could be varied throughout a wide range and still produce satisfactory results, or some other shape of undercut bearing surface could be employed;

The swivel member 22 is in the form of a ring whose outer peripheral bearing surface is complementary to the inner peripheral face of the bearing ring 21, the ring 22 conseqeuntly being wider at its base than at its upper end. In cross section, the swivel ring is preferably channel-shape with its lower end open, to save weight. A pair of spaced upstanding ears 23 are secured to the top ofcable plate 12, as illustrated in Figs. 2 and 3, the material of the container 16 terminating at the outer periphery of the flange 20 of bearing ring 21. A central, circular opening 26 extends through the inside cable plate 12 for filling and emptying the container and is surrounded by an annular series of screw-threaded recesses 27 which may be used to bolt a cover (not shown) over the open-' ing 26when it is desired to seal such opening. For general use, however, a tubular fitting 28 has its end threaded into opening 26, by means of a polygonal nut surface 29 on the fitting. A groove 30 is provided adjacent the upper end of the fitting to facilitate securing a suitable cap element or valved coupling element to the fitting. The fitting 28 may have any suitable valve means for filling or emptying the container, such as the usual spring loaded poppet valve inside the fitting, so as to be opened by pressure of a filling nozzle inserted in the upper end of the fitting. The particular type of fitting 28 is optional so long as it does not interfere with free swiveling action of swivel ring 22 within the bearing ring 21.

It will be seen that the outer retaining ring 16 is bolted to the inner cable plate 12 and is spaced therefrom by the material of the container which is compressed therebetween. The bearing ring 21 is so firmly secured to retaining ring 16 as to be substantially an integral part thereof, but the lower surface of its flange 20 extends past the material of the container and rests upon or close to the cable plate 12. The swivelring 22 also rests upon the cable plate 12 and when the botls 17 are tightened to draw cable plate 12 and retaining ring 16 together, the inclined inner bearing surface of the bearing ring 21 securely holds the swivel member 22 in place against the cable plate while permitting free rotational movement of the swivel member within the bearing ring.

In operation, a swivel assembly is provided at each end of the container 10 as shown in Figure 1, but only one fitting 28 is necessary, and the opening 26 at the opposite end of the container can be sealed by means of a cap.

or plate secured in place by bolts threaded into recesses 27. The container may be filled through fiitting 28, lifted by hoists or cranes attached to chains 25 for placement in transportation vehicles or wherever desired, secured in place by means of cables or the like attached to cables 25, dropped by parachute connected to cables 25, or placed upon its side and rotated about its axis by pulling upon chains 25 at each end of the container. One or more of the containers may be connected to a vehicle and towed about, even over very rough terrain without injury to the container or its contents, and when the containers have been emptied they may be collapsed and stored or transported in a very small space.

The arrangement of the bearing rings and swivel rings at each end of the container permits ready handling and moving of the container while leaving the fitting 28 accessible through the open center of the swivel ring 22. Due to the axial arrangement of the opening 26 and fitting 28, and the spacing of the swivel ring from the fitting and filling opening, the container may be moved or rolled about Without damage to the fitting 28 and without rendering the fitting inaccessible, even in the towing position of the container. The arrangement of the hearing ring 21 clamped in place by bolts 17 maintains the swivel ring in position against the weight of the filled container when it is lifted by means of chains 25 and yet permits easy rotation of the bearing ring about the swivel ring when the container is towed, In towing, the entire container rotates about the two swivel rings and couplings.

While the preferred embodiment of the invention has been shown and described, it is to be understood that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. In a flexible container, a swivel assemble carried by the container and including an annular swivel element, means carried by the swivel assembly to rotatably secure the swivel element to the swivel assembly exteriorly of the container, a filling and emptying fitting carried by the swivel assembly to project axially through the annular swivel element and out of contact therewith, and a coupling member secured to the annular swivel element whereby the container may be secured by the coupling member while capable of rotation about the swivel element and its coupling member.

2. In a fiexible container having an opening, a swivel assembly comprising a plate secured to the margin of the container opening and closing said opening, an annular swivel element, means to rotatably secure the swivel element to the plate, a filling and emptying fitting carried by the plate in a position to project axially through the annular swivel element whereby relative rotation between the container and plate with respect to the swivel element will be unimpeded by the fitting which will maintain its position with respect to the swivel element, and a coupling member secured to the annular swivel element.

3. In a flexible, rotatable container having axial openings at its ends, a swivel assembly at each end of the container, each such assembly comprising a plate secured to the material forming the margin of a container opening to close such opening, an annular swivel element,

means to rotatably secure the swivel element to the plate exteriorly of the container, a coupling member secured to the annular swivel element, and a filling and emptying fitting carried by one of the plates in a position to project axially through the adjacent annular swivel element.

4. The, device as defined in claim 3 wherein the two plates are connected interiorly of the container by reinforcing means.

5. In a rotatable flexible container having axial openings at each of its ends, a swivel assembly at each end of the container, each of such assembliescomprising a plate clamped to the material forming the margin of a container opening to close such opening, an annular swivel element, means to rotatably secure the swivel element to the plate exteriorly of the container, said securing means including an annular undercut bearing surface in engage- I ment with a complementary bearing surface on the swivel element, a coupling member secured to the annular swivel element, and a filling and emptying fitting carried by one of the plates in a position to project axially through the adjacent swivel element and its securing means.

6. The device defined in claim 5 wherein the two plates of the swivel assemblies are connected interiorly of the container by flexible, substantially inextensible reinforcing means.

7. In a flexible, rotatable container having an opening, a two-member swivel assembly closing said container opening and comprising a stationary member secured to the material surrounding the container opening, a rotatable member operatively connected to the stationary swivel member to be freely rotatable with respect thereto while being held against movement in a direction away from said stationary member, one of said swivel members being ring-shaped and the other swivel member having an opening axially of the ring-shaped member and of less diameter than the interior diameter of the ring-shaped member, a filling and emptying fitting carried in said axial opening in the swivel member out of contact with the ring-shaped member, and a coupling element connected to the rotatable swivel member.

8. In a flexible, rotatable container having axial openings at each of its ends, a swivel assembly at each end of the container, each assembly comprising a plate of larger diameter than the adjacent container opening and adapted to close said opening from the interior thereof, an annular clamping ring surrounding the container opening exteriorly of the container, means to firmly secure the clamping ring to the plate with the material of the container surrounding the container opening clamped between the clamping ring and the plate,'an annular hearing ring secured adjacent the plate within the inner periphery of the clamping ring and provided with an undercut bearing surface, and an annular swivel ring having a bearing surface complementary to and closely engaging the undercut bearing surface of the bearing ring, whereby the swivel ring is held against movement away from the 5 plate by the undercut portion of the bearing ring while References Cited in the file of this patent freely rotatable with respect to the bearing ring and plete, UNITED STATES PATENTS a couphng member secured to the annular swivel ring of each swivel assembly, and a filling and emptying fitting 1,3 5,4 7 Traynor Mar. 30, 1920 communicating with the interior of the container, 5 1, 39,329 Randolph Dec, 19, 1922 9. The device of claim 8 wherein a flexible reinforcing 50,7 Lobl Nov. 29, 1927 member Connects the plates of the swivel assemblies 1,988,385 Kiel Jan. 15, 1935 interiorly of the container. ,612,924 Cunningham Oct. 7, 1952 10. The device of claim 8 wherein the filling and 2,757,025 Noyes et a1. July 31, 1956 emptying fitting extends from the plate of one swivel 10 2,779,479 Cohen Jan. 29, 1957 assembly axially of its swivel ring. 2,787,309 Cunningham Apr. 2, 1957 

